I just got this awesome idea, check it out (:
Today I briefly asked a friend of mine: free for coffee? And the symbol just came to me: an inmate coffee cup. Why, you ask?
"Free for coffee" could have two meaning: one, the obvious question and the second is like a dare "free(dom) for coffee!"
It's a bit too confusing I think, I didn't see a jailed coffee cup at first, I just saw a coffee cup similar to the old at&t logo with some strange stuff hanging off of it. The idea is neat, it just needs to be sketched out more to make it cohesive with the type/symbol.
Yeah, until i read the description, I didn't get any of what you were intending, just a confusing mess.
To make things very slightly better you could add a question mark - 'free for coffee?' as it would suggest more, but ultimately this is a fail in my opinion.
Try to refine your ways/devices/vehicles of presenting the ideas.